How to deal with a Narc when you have kids

My husband and I have been separated for over a month now. We have a 5 year old son and I am 8 months pregnant with our second. I caught him cheating and left thinking he would follow and try to fix things, this is before I discovered he was a Narc.

He was lying the whole time telling me it was over between them and that he loved me but need some time to get things back on track before baby gets here. I believed him until I went to our house after he got of work and the OW was there!!!! All of mine and my sons belongs are still there! 3 hours before this he was texting me how much he missed me and our son!

Of course now that he can't deny it because I caught him red handed he turned evil. Said nasty things to me about being with her and I slapped him in the face and left. Got a call about an hour later from the cops saying he called for domestic violence. Case is now pending.

Anyways I am so unsure what to do with this unborn baby coming. We are still married...I have filed for child support for my son because I am unemployed, He was my only income. I can file for divorce and he hasn't yet. I don;t know if i should tell me when i have her, have him there or just forget about it.

He has seen our son 3 days out of the last 3 weeks!